turn your back on someone

turn (one's) back on (someone or something)

To ignore, disregard, or exclude someone or something; to abandon, give up on, or forsake someone or something. It's clear that the company has turned its back on customers. After becoming a successful writer, Jim turned his back on all the people he used to know back home.
See also: back, on, turn
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

turn your back on someone

COMMON If someone turns their back on you, they ignore you and refuse to help you. We appeal to this conference — do not turn your back on the poor. Our job is to protect children and we can't just turn our backs on them.
See also: back, on, someone, turn
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012
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